Which is more energy-efficient: water floor heating or electric floor heating? It might surprise you.

In southern China, due to the lack of centralized heating systems, many users, including a significant number of ground heating businesses, believe that electric ground heating is energy-intensive, whereas using gas-powered water ground heating is more economical.

You might argue that electric water heaters consume more energy than gas ones. Taking Nanjing, Jiangsu Province as an example, the sales prices for gas at first, second, and third tiers are 3.03 yuan/m³, 3.64 yuan/m³, and 4.24 yuan/m³ respectively.

Nanjing residential electricity charges are categorized as:

(1) Nanjing residents' tiered electricity pricing for residential power consumption

Annual electricity consumption ≤ 2760 kW·h; electricity rate for less than 1 kV is 0.5283 yuan/kW·h, and for 1-10 kV is 0.5183 yuan/kW·h.

2760kW·h < annual electricity consumption ≤ 4800kW·h, voltage below 1kV is priced at 0.5783 yuan/kW·h, 1-10kV is priced at 0.5683 yuan/kW·h.

Annual electricity consumption > 4800 kW·h, below 1 kV electricity rate is 0.8283 yuan/kW·h, 1-10 kV electricity rate is 0.8183 yuan/kW·h.

(II) Residential Peak-Off-Peak Time-of-Use Electricity Rates

Residential electricity rates are 0.5583 yuan/kW·h during peak hours (8 am - 9 pm), and 0.3583 yuan/kW·h during off-peak hours (midnight - 8 am, 9 pm - midnight).

The peak-valley electricity price policy is on the path of popularization and reform, with promising future ahead.

To maintain fairness, we are temporarily calculating based on the high-value electricity rate of 0.8283 yuan/kW·h and gas price of 4.24 yuan/m³.

1 cubic meter of gas costs 4.24 yuan and contains 8600 KAL of heat. In contrast, 1 kilowatt-hour of electricity costs 0.8283 yuan and provides only 860 KAL of heat. This means that you get 10 times the energy heat for a price that is 5 times higher than electricity, almost twice the cost of gas for the same amount of heat.

I personally use electric underfloor heating in Nanjing, and so do my neighbors of the same space using water underfloor heating. The temperature of the underfloor heating in winter is generally around 22℃. However, the actual cost of use is roughly the same, and sometimes even a bit cheaper with electric heating. Additionally, I've compared the costs of use for many water and electric underfloor heating customers, and they are generally similar. How can this be explained?

1. Heat efficiency concerns

The HOCHTIEF electro-thermal floor heating system can generally provide comfortable heating with just two hours of operation. However, water-based floor heating, due to its slow warming, and the relatively poor thermal insulation of building walls and doors and windows in southern regions, requires 24 hours to heat up. It's not until the next day that warmth is felt, so it can't be easily turned off and must remain on continuously. In other words, using gas, for the same cost, you get nearly double the heat compared to electricity, which is essentially wasted.

Therefore, in actual application, the cost of using electric underfloor heating and gas-powered water underfloor heating is almost equivalent. The HOCHTIEF Hochtief electric underfloor heating system is installed independently in each room, with no connection to other rooms, and operates only where it's needed. However, water underfloor heating is different; if you use the master bedroom but the manifold is located elsewhere, the pipes must pass through the living room to reach the bedroom. The heat lost during the pipe journey might be what you need, or it might not be. If it's not needed, it's a significant waste, as the hot water hasn't reached the room before its temperature has dropped. It's a bit like the national initiative to reduce plastic waste in recent years, which also contributes to reaching carbon peak and carbon neutrality.

4. Maintenance and care issues

HOCHTIEF's electric underfloor heating system is a no-brainer, both theoretically and practically. However, the difference is far from a 1x cost gap. Moreover, even if some costs are saved, the trade-off is lower comfort compared to underfloor heating, more indoor space usage, and the same unavoidable maintenance issues and efficiency loss.

Haugheitif, let the temperature adapt